Automatic switch-lock.



C. E. DUFFIE.

AUTOMATIC SWITCH LOCK.

APPLICATION rum) JULY 25, 1907.

908,979. Patented Jan. 5, 1909.

CHARLES E. DUFFIE, OF OMAHA, NEBRASKA.

AUTOMATIC SWITCH-LOCK.

Specification of Letters Patent.

Patented Jan. 5, 1909.

Application filed July 25, 1907. Serial No. 385,501.

To all whom it may concern:

Be it known that I, CHARLES E. DUFFIE, a citizen of the United States, residing at Omaha, in the county of Douglas and State of Nebraska, have invented certain new and useful Improvements in Automatic Switch- Locks, of which the following is a specification.

One of the objects of my invention is to provide means for automaticall looking a railway switch upon the approach of a train.

Another object of my invention is to obtain an automatic unlocking of the switch while the train is covering a certain section of the track before reaching said switch.

The invention also relates to the other improvements in switch locks hereinafter set forth.

In the accompanying drawings, Figure l is a diagrammatlc representation of an automatic locking system embod ing m invention. Fig. 2 is a longitudina centra section of the switch lock proper showing the switch unlocked and in the open osition. Fig. 3 is a similar sectional view s owing the switch closed and locked.

In the apparatus herein shown, I provide three independent track circuits located in front of the switch, and a fourth circuit operating the switch lock, and controlled by the several track circuits. I shall refer to the three track circuits as A, B and C. The fourth or switch-lock circuit I shall term circuit D. The track is divided into sections included in their respective track circuits, said sections being insulated from each other and from the rest of the track in any suitable manner. The two track-sections nearest the switch are each preferably 100 feet long, the third-track section preferably extending to a point opposite the semaphore or other signal device operated in connection with the railway. In practice therefore the latter track section is about one-half mile long. The circuit 0 includes a relay 1, electrically connected with the traffic rails 2 close to the switch points, and a battery 3 or other current-producer connected with the opposite ends of the rails 2. The track circuit B is similar to the circuit C and includes the relay 4, rails 5 and the battery 6. The circuit A comprises the relay 7, the rails 8 and the battery 9. The switch-lock circuit'D includes a battery 10, a solenoid 11, and the armatures 12 and 13 of the track circuit relays 1 and 7. The armature 14 of the relay 4 is connected in parallel with the armature 13.

The switch-lock proper comprises a box or casing 15 located preferably in line with the switch points, and receiving a rod attached to and moving with said switch oints. Within said boX is a guide block 17 aving a guideway 18 therein through which said rod passes. A recess 19 in said guide block intersects said guideway. Within the box 15, and preferably fixed to the cover 20 of said boX directly over said recess, is the solenoid 11. Said solenoid is r0 )erly insulated and included in the switc -block circuit D. To the core 21 of said solenoid a ate 22 is attached adapted to drop, on the re easing of said core, into the recess 19. The recess is located at such a point with reference to the rod 16 that when the gate 22 is in its lower or operative position said rod is held from longitudinal movement and the switch consequently locked in the closed position. This 0 eration is fully shown in Figs. 2 and pon energizing the solenoid the core is again withdrawn and said switch may then be operated.

Assuming the switch to be closed, the operation is as follows: Upon a train approac 1- ing the switch from a distance it will enter upon track circuit A. As soon as the first pair of Wheels enters upon the rails S the battery 9 will be short-circuited, (lenergizing the relay 7, releasing the armature 14 and opening the switch lock circuit D. The solenoid 11 being thus de'e'ner ized, the gate 22 immediately drops behind the rod 16, looking the switch in the closed position. Upon the train'passing onto the rails 5 the battery 6 is shortcircuited, denergizing the relay 4 and releasing its armature 14. The switch -block circuit D is thereby closed through said relay and its relay points, withdrawing the gate 22 and unlocking the switch. If it be desired to switch the train onto the siding, the switch may now be thrown. When the train reaches the rails 2, the battery 3 is short-circuited, deenergizing the relay 1 and again breaking the switch-lock circuit. If closed, the switch is again looked through the denergizing of the solenoid 11. Should the train be traveling at a high rate of speed the time occupied in covering the 100 feet of track circuit B would not allow the unlocking of the switch, due to the naturally sluggish movement of the weighted core. As soon as the last pair of wheels has left the rails 2, the relay 1 again receives current from the battery 3 and closes the switch-lock bination, a switch member; a lock for said circuit D, thus automatically unlocking the switch member; means for operating said switch. The track circuit 0 extending close to the switch-points, the switch will not be unlocked until after the entire train has passed said switch.

It will be observed that the apparatus herein described operates on the closed-circuit principle, any derangement ol' the circuits and circuitapparatus automatically locking the switch to the main linef l l l l i The gate 22 is freely movable vertically in 5 its recess 19, and instantly drops into locking position when the solenoid 11 is deprived of power.

It is evident that various changes may be made in the embodiment herein shown with- 5 out departingfrom the spirit and scope of my invention, therefore no undue limitation should be understood irom the foregoing detailed description.

I claim as my invention:

1. In a switch-locking apparatus, in com- 2 bination, a switch member; a lock for said swltch member; an electric circuit comprismg means tor operating said lock; tra1n-opl l l erated means for opening and closing said locking position; a normally closed circuit circuit; and means for closing a shunt in said circuit around sald tram-operated means.

2. In a switch-locking apparatus, in coniblnation, a switch member; a lock for said switch member; an electric'circuit comprising means for operating said lock trainoperated means for opening and closing said circuit; and train-operated means for closing a shunt in said circuit around said first mentioned train-operated means.

l l I 3. In a switch-locking apparatus, in. com- 1 blnation, a switch member; a lock tor said i switch member; an electric circuit comprrsing means for operating said lock; a track circuit comprising means for opening said first mentioned circuit; and a track circuit 1 comprising means for closing a shunt in said first mentioned circuit around said circuitopening means.

4. In a switchdocking apparatus, in combination, a switch member; a lock for said switch member; a switch-lock circuit; two track circuits comprising means for opening said switch-lock circuit; and an intermedilocl; to lock said member upon the approach of a train; means for operating said lock to unlock said member upon a further approaching movement of the train; and means for again operating said lock to lock said member upon an additional approaching movement of the train.

6. In a switclilocking apparatus, in combination, a switch member; a lock for said switch member; two track circuits for operating said lock to lock said member; and an intermediate track circuit for operating said lock to unlock said member.

7. In a switch-locking apparatus, in combination, a switch member; a vertically movable gate adapted to lock said switch member against movement; an electro-magnet for moving said gate upwardly out of locking position; and means for energizing and deenergizing said electro-magnet.

8. In a switch-locking apparatus, in combination; a switch member; a vertically movable gate adapted to lock said switch member against movement; an electro-magnet for moving said gate upward out of in which said electro-magnet is included;

and means for opening and closing said circuit.

9. In a switch-locking apparatus, in combination, a switch member; a gravity-mow able gate for locking said switch member against movement; an electro-magnet for movin said gate out of locking position; a norma ly closed circuit in which said electromagnet is included; and means for opening and closing said circuit.

10. In a switch-locking apparatus, in combination, a casing having a guide-block therein, said block having a horizontal guide opening therein; a switch member reciprocable in said. guide opening; a gravitymovable gate for locking said switch member against reciprocation; an electro-magnet ate track circuit comprising means for closmg a shunt in said sw1tchlock circuit around i the circuit-opening means in one of said first mentioned track circuits.

5. In a switch-locking apparatus, in comfor moving said gate upward out oflocking position; a normally closed circuit in which said electro-magnet is included; and train operated means for opening and closing said circuit.

CHARLES E. DUFFIE.

I/Vitnesses WILL H. THoMPsoN, JOHN F. STOUT. 

